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boreus infragroup

Diagnosis:
Haradon 1985:

Diagnosis.—An infragroup of nominate subgenus Paruroctonus differentiated by combination of: (1) cheliceral fixed digit with inferior canna extending proximally at least to level of bicusp (see Gertsch and Soleglad 1966: fig. 39); (2) cheliceral movable digit with superior distal tine elongate and curved, inferior distal tine length/superior distal tine length ratio less than 3.0; (3) carapace length/cheliceral fixed digit length ratio 5.5-9.0; (4) basitarsus III with six or more superior setae, arranged in distal plus proximal rows (4+2 to 5+2) or in essentially single file; (5) pectinal teeth in males 24-39 (except 20-23 in some populations of P. bantai and P. baergi, or rarely 23 in several other species), females 18-24 (except some populations 16-17 in P. bantai and 13-17 in P. baergi, or rarely 17 in several other species); (6) pedipalp movable finger length/palm length ratio in adult males and females 1.1-1.6; (7) carapace length/pectine length ratio in adult males 0.8-1.0, adult females 1.2-1 .4 (except 1.6-1.8 in P. utahensis); (8) humerus with three inframedial macrosetae on proximal 3/5 of internal surface (except two in P. baergi); (9) pedipalp primary denticles, excluding proximal row, total 25-90 fixed finger, 35-103 movable finger (rarely 35 or 36); (10) adult carapace length generally 4.5-6.0 mm in males, 5.0-7.0 mm in females.

Distribution: Western North America, southern Canada southward into northern Baja California Norte, Sonora and Chihuahua in México. (Haradon 1985)

Included taxa: The boreus infragroup comprises four primarily allopatric elements, differentiated as follows and in Table 1. (Haradon 1985)

BOREUS MICROGROUP. Diagnosis : combination of carapace length/cheliceral fixed digit length ratio 7 .0-9 .0 ; basitarsus II with mrs seta . Distribution : Rocky Mountains region westward to Pacific coastal mountains (excluding northwest coast), southern Canada southward to northern Arizona and northern Baja California Norte (excluding Mojave and Sonoran Deserts). Included taxa : P. boreus (Girard, 1854) ; P. silvestrii (Borelli, 1909) ; P. bantai (Gertsch and Soleglad, 1966) ; P. bantai Saratoga, n . ssp . ;P. arnaudi Williams, 1972 .

BECKI MICROGROUP. Diagnosis : carapace length/ cheliceral fixed digit length ratio 5 .5-6 .5 . Distribution : Western and southern Great Basin, southwestward through Mojave Desert to San Jacinto Mountains and edge of Colorado Desert in California. Included species : P. becki (Gertsch and Allred, 1965).

XANTHUS MICROGROUP. Diagnosis : pedipalp primary denticles, excluding proximal row, total 82-90 on fixed finger, 98-103 on movable finger ; pedipalp movable finger length/palm length ratio 1 .4-1 .6 in both sexes ; pedipalp fingers multi-scalloped in adults of both sexes (see Gertsch Soleglad 1966 :fig . 32) ; telotarsus III with six or seven retrosuperior setae . Distribution : Sand dunes, southeastern California and extreme northwestern corner of Sonora . Included species : P. xanthus (Gertsch and Soleglad, 1966) .

BAERGI MICROGROUP. Diagnosis : combination of carapace length/ cheliceral fixed digit length ratio 7 .0-9 .0; pedipalp primary denticles on movable finger in six rows; basitarsus II without mrs seta . Distribution : Loose sandy soils, primarily dunes, associated with Colorado River and Rio Grande drainages, from southern Utah to northern México. Included species: This microgroup, named after P. baergi (Williams and Hadley, 1967) , and including P. utahensis (Williams, 1968b), is discussed in detail by Haradon (1984a) .
                                                                                      

Key:
Haradon 1985:

Table 1 .- Diagnostic characteristics of the four microgroups constituting the boreus infragroup of the nominate subgenus Paruroctonus.Haradon 1985
Character		xanthus	becki	boreus	baergi
Carapace length/cheliceral fixed digit length		7.0-9.0	5.5-6.5	7.0-9.0	7.0-9.0
Pedipalp movable finger length/palm length		1.4-1.6	1.1-1.3	1.1-1.2	1.1-1.2
Pedipalp primary denticles, rows on movable finger less proximal row, fixed finger                                      movable finger		7 >80 >90	6-7 <80 <90	6 <80 <90	6 <80 <90
Pedipalp fingers, scalloping: (A) not, (B) proximally only, (C) multiscalloped	♂ ♀	C C	A A	A,B A	B A
Basitarsus II mid-retrosuperior seta (A) present (B) absent		B	A	A	B
Basitarsus III superior setae: (A) in distal plus proximal rows, (B) in single file		10-11 B	6 A	6 A	7-11 A,B
Telotarsi II-IV retroinferiorterminal setae		2	1	2	2
Telotarsi III retrosuperior setae		6-7	2	2	2-4

Notes:
Haradon 1985:

Key: Cheliceral fixed digit inferior carina extends proximally at least to level of bicusp; carapace length/cheliceral fixed digit length ratio 4.2 or more; Pectinal teeth 24/24 or more in males and 17/18 or more in females and 37 or more primary denticles (less proximal row) on pedipalp movable fingers, or if fewer pectinal teeth then either (1) dorsal metasomal setae I-IV 0,0,0,1, or (2) no mrs seta on basitarsus II boreus infragroup

Comparisons:: The gracilior infragroup (above) differs in characters 1-4; the stahnkei infragroup (below) differs primarily in character 5, but also significantly in 6-10. Exceptional males with fewer than 24/24 and females with fewer than 17/18 pectinal teeth differ from the stahnkei infragroup in having 35 or more primary denticles (less proximal row) on pedipalp movable finger in combination with either dorsal metasomal setae I-IV 0,0,0,1 (P. bantai), or mrs seta absent on basitarsus II and either three internal inframedial macrosetae on humerus or one retromedial seta on telotarsus III (baergi group).

Remarks.—The boreus and gracilior microgroups, where sympatric with the arenicolous baergi microgroup, occupy more compact soils ; the boreus microgroup, where sympatric with the becki microgroup, tends to occupy higher elevations .